Home runs per nine innings
In baseball statistics, home runs allowed per 9 innings pitched (HR/9IP or HR/9) or home runs allowed per nine innings (denoted by HR/9) is the average number of home runs given up by a pitcher per nine innings pitched. It is determined by multiplying the number of home runs allowed by nine and dividing by the number of innings pitched.[1] Pitchers with high fly ball rates are more likely than pitchers with high ground ball rates to have high HR/9 rates.[1]
Leaders
The career leaders in HR/9IP through 2018 were Jim Devlin (0.0448), Al Spalding (0.0468), and Reb Russell (0.0488).[2]
There were 87 single-season leaders in HR/9IP through 2018 who had pitched a season without giving up a home run.[3] All played prior to 1927.[3]
The active leaders in HR/9IP through 2018 were Clayton Kershaw (0.6225), Adam Wainwright (0.6755), and Charlie Morton (0.7682).[4]
References
- What is a Home Runs Per Nine Innings (HR/9)? | Glossary | MLB.com
- Career Leaders & Records for Home Runs per 9 IP | Baseball-Reference.com
- Single-Season Leaders & Records for Home Runs per 9 IP | Baseball-Reference.com
- Active Leaders & Records for Home Runs per 9 IP | Baseball-Reference.com